Till now, we’ve discussed the fierce master, voltage, who forces the charge to move around in a circuit. But, we didn’t really talk about these charges that move around in the circuit. But don’t you worry! We’ve got them covered in this topic!
Let’s start by considering our water system. Due to the pressure of the pump, water continuously flows in the pipe. This stream of water has very small particles known as water molecules; these molecules together flow around the pipe and create this stream. This flow of water is known as a current. Since the water pump system is similar to an electric circuit, the concept of current is the same in both. In an electric circuit, the current is nothing but the flow of electric charges in the electric pipe, which is called a wire. But, what are these charges? Where do they come from?
Everything in this universe, be it living or non-living, right from the small sand grains to biggest stars and planets, is made of extremely small particles known as atoms. Atoms are further made up of even smaller particles known as charges. The flow of these charges in a circuit is known as current.
In objects known as conductors, there are a lot of free charges, i.e. charges that can move easily whenever we connect a power source. A wire is also a conductor; that is why current, or charges easily flow through it. But remember that you should never touch a wire with current flowing through it, especially when it isn’t covered; it will give you a shock, sometimes so dangerous that you might even die.
Another important thing to keep in mind while talking about current is the direction of its flow; conventionally, it is from the positive terminal of the power supply to its negative terminal.